Directional system for landing of aircraft



Dec. 15, 1936.

A. LEIB 2,064,171

DIRECTIONAL SYSTEM FOR LANDING OF AIRCRAFT Filed Dec. 2, 1933 INVENTOR AUGUsT LEIB BY w gm ATTORNEY Patented Dec. 15, 1936 UNITED STATES PATENT OFFIQE DIRECTIONAL SYSTEM FOR LANDING OF AIRCRAFT Germany Application December 2, 1933, Serial No. 700,756 In Germany December 2, 1932 6 Claims.

This invention relates to an improved transmitter arrangement comprising a beam-transmitting antenna for blind landing of airplanes.

It is an object of my invention to provide a radio beam transmitter having an antenna and beam reflecting system arranged to propagate a landing beam substantially from the ground level of an airport and in a direction suitable to be followed by an airplane when making a landing.

My invention will be hereinafter described with the aid of the accompanying drawing in which Figure 1 shows diagrammatically and in elevation an arrangement of my improved radio beam transmitter; and

Fig. 2 shows a modification of my invention in which the transmitter is preferably located in a pit beneath the surface of the landing field.

Heretofore in order to obtain the projection of a landing beam from a suitable point on or near the landing field, it has been necessary to locate the transmitter in a position where it would be liable to be run into by a plane when making a landing.

This danger of collision can be obviated according to my invention if at the point on the landing field a-b where the beam 0 is to be emitted, there is arranged a ground reflector s which is irradiated, as it were, from the radiator d mounted outside the zone of possible collision.

The ground reflector most suitably may consist of a metallic reflector, though under certain circumstances the ground surface itself, if of suitable properties, may constitute the ground refiector.

Referring to Fig. 1, 8 denotes the ground reflector, and d the radiator, the latter most preferably being mounted in the rear of the landing field at a point where no landings ever take place, and whose directional beam cl is made to impinge upon the reflector, whence it is thrown back in the form of the beam c. The directional action of the radiator is symbolically indicated in the drawing by a parabolic mirror, though it will be understood that any other directional transmitter may be used. It is evident that the reflective action of the ground mirror will be so much more precise, the shorter the waves used. Thereflector s, however, could be used also for the reflection of several beams.

The arrangement hereinbefore disclosed offers the further merit that the antenna may be mounted at closer proximity to the generator so that the feed cables or leads can be made shorter.

Another possible embodiment is illustrated in Fig. 2. The radiator d is here accommodated below ground in a ditch or pit, and so is the refiector s. The latter is orientated at a certain angle, say, vertically or nearly so. The pit wherein the radiator and the reflector are placed, where required, could be partly or wholly covered or filled with sufiiciently strong (solid) material such as lattice work or glass indicated by the dotted line G.

I claim:

1. A radio transmitter system for facilitating a blind landing of aircraft on a landing field, comprising a radiating antenna in combination with means located within a pit in the ground of said landing field for focussing the energy emitted by said radiating antenna in a concentrated beam, and a reflector located in the path of said beam, said reflector being so positioned that the emitted energy from said antenna is thrown back at a useful angle of inclination to the ground for guiding said aircraft to a safe landing.

2. A system in accordance with claim 1 and having a covering of lattice-Work or the like over said pit, and further characterized in that the reflector is located on one side of said pit beneath said lattice-work while the radiating antenna is located on the opposite side of said pit beneath said lattice-work.

3. In a directional radio beam transmitting system, a source of radio energy, means including a directional antenna system for emitting a concentra-ted beam of said energy, said antenna systern being located adjacent a landing field and yet beyond the landing path of an airplane, and means including a radio beam reflector located in the path of said concentrated beam for causing said energy to be directed slopingly upward from approximately the same point on said landing field as it is desired to have an airplane make ground contact.

4. A system in accordance with claim 3 and having said directional antenna system located above the level of said landing field.

5. A system in accordance with claim 3 and having said directional antenna system located below the level of said landing field.

6. A system in accordance with claim 3 and having a pit beneath the surface of said landing field in which to protectively locate said directional antenna system and said reflector, said pit being roofed over to prevent the dropping of an airplane into the same.

AUGUST LEIB. 

